1. Field of the Invention
The present invention relates in general to heat exchangers of motor vehicles, and more particularly to a tank of the heat exchangers, which generally comprises a tank body of clad metal, a pipe member of clad metal, a header plate member of clad metal and end plates of clad metal which are all hermetically secured to one another by means of brazing.
2. Description of the Prior Art
In order to clarify the task of the present invention, some conventional tanks of heat exchangers will be described with reference to the drawings.
Referring to FIG. 41, there is shown a conventional tank of heat exchanger, which is disclosed in Japanese Utility Model First Provisional Publication 60-2195. The conventional tank comprises a tank body 1 which has a pipe inserting opening 1a provided by means of a burring reamer. A pipe member 2 is inserted into the pipe inserting opening 1a having its leading end abutting on an inner surface of the tank body 1 through a seating plate 3. However, usage of the seating plate 3 brings about a troublesome and time consuming work for producing the tank. Furthermore, due the nature of the burring reamer, the tank needs a height xe2x80x9cHxe2x80x9d much greater than the diameter xe2x80x9cDxe2x80x9d of the pipe member 2, which causes a bulky construction of the tank.
Referring to FIG. 42, there is shown another conventional tank of heat exchanger. The conventional tank comprises a tank body 1 produced by using a deep drawing technique, and a header plate member 4 brazed to the tank body 1. For facilitating the assembly, the header plate member 4 is partially fixed or welded to the tank body 1 before carrying out the brazing. However, in this conventional tank, different types of dies are needed depending on sizes and types of the tank produced by the deep drawing technique, and thus cost of the tank increases inevitably. If the tank is designed for radiators, the tank is obliged to have a larger height and longer structure making the deep drawing much difficult. Furthermore, the longer structure of the tank makes the brazing between the tank body 1 and the header plate member 4 much difficult. Furthermore, for the partial attaching between the tank body 1 and the header plate member 4, the parts 1 and 4 have to have complicated engaging and engaged portions 1a and 4a which are to be mutually engaged, which also brings about increase in production cost of the tank.
Referring to FIG. 43, there is shown still another conventional tank of heat exchanger, which is of a seam welded pipe type made of aluminum. The tank shown in FIG. 42 has a rectangular cross section. However, in this conventional tank, due to the tubular shape, formation of the opening in the tank for receiving and holding the pipe member needs a troublesome and consuming manual work.
Referring to FIGS. 44 and 45, there is shown a further conventional tank of heat exchanger, which is made of aluminum. The tank shown in the drawings comprises an aluminum tank body 1 having a generally C-shaped cross section and an aluminum header plate member 5 fitted to an open portion of the tank body 1. To both sides of a unit consisting the tank body 1 and the header plate member 5, there are fixed aluminum end plates 6 (only one is shown) respectively. As is seen from the drawings, each end plate 6 is formed with a rectangular recess 6a into which the corresponding end of the unit is press-fitted. The recess 6a of the end plate 6 and the end of the unit are brazed at xe2x80x9cRxe2x80x9d in a furnace. However, as is seen from FIG. 45, if the press-fitting of the unit to the end plate 6 is too hard due to a possible dimensional error therebetween or the like, the tank body 1 becomes deformed as is shown by phantom lines. Of course, in this case, brazing of such deformed portion and the end plate is not adequately carried out.
Referring to FIG. 46, there is shown a conventional structure for holding a radiator 7 to a motor vehicle (not shown) through lower and upper mount rubbers 12 and 15. The radiator 7 comprises upper and lower tanks 8 and 9 of plastics and a core structure 10 interposed between the upper and lower tanks 8 and 9. The lower tank 9 has at its lower surface mounting pins 11 by which the lower mount rubber 12 is held. The lower mount rubber 12 is held by a lower bracket 13 extending from the vehicle body. The upper tank 8 has at its upper surface mounting pins 14 by which the upper mount rubber 15 is held. The upper mount rubber 15 is held by an upper bracket 16 extending from the vehicle body. Due to provision of the upper and lower mount rubbers 15 and 12, undesired transmission of vibration of the vehicle body to the radiator 7 is lowered or at least minimized. FIG. 47 shows a conventional technique for fixing each mounting pin 14 or 11 to the upper or lower tank 8 or 9. For this fixing, the tank 8 or 9 is formed with an opening 8a, and each mounting pin 14 or 11 is formed with a forked projected portion 14a. The forked projected portion 14a is put in the opening 8a and then brazing is practically applied to mating portions therebetween. However, this pin fixing work is troublesome. Furthermore, satisfied brazing is not obtained by the pin due to a non-negligible difference in heat capacity between the mounting pin 14 or 11 and the tank 8 or 9. Of course, the unsatisfied brazing tends to induce leakage of cooling water from the tank.
It is therefore a main object of the present invention to provide a tank of heat exchanger, which is free of the above-mentioned drawbacks.
It is an object of the present invention to provide a tank of heat exchanger, wherein a pipe member is readily and assuredly connected to a tank body.
It is another object of the present invention to provide a tank of heat exchanger, which is easily manufactured at a reduced cost.
It is still another object of the present invention to provide a tank of heat exchanger, wherein end plates are assuredly brazed to ends of a unit including a tank body and a header plate member.
It is a further object of the present invention to provide a tank of heat exchanger, wherein mounting pins are readily and assuredly fixed to the tank.
According to a first aspect of the present invention, there is provided a tank of heat exchanger, which comprises a tank body made of a metal, the tank body being shaped like a channel member including a base wall and opposed side walls between which the base wall extends; and a metal member that is hermetically secured to a given portion of the tank body by partially welding the metal member to the given portion and then brazing the metal member to said given portion.
According to a second aspect of the present invention, there is provided a tank of heat exchanger, which comprises a tank body made of a clad aluminum plate, the tank body being shaped like a channel member including a base wall and opposed side walls between which the base wall extends; a circular opening formed in one of the side walls; a pipe member of a clad aluminum plate, the pipe member having a circular flange which is brazed to the one of the side walls in a manner to provide a fluid communication between the interior of the tank body and the interior of the pipe member through the circular opening; a header plate member of clad aluminum plate to which a core structure of the heat exchanger is connected, the header plate member having therealong respective flanges, the header plate member covering a longitudinally extending open portion of the tank body by having the flanges thereof brazed to inner surfaces of the opposed side walls of the tank body; and end plates of clad aluminum plate, which are brazed to longitudinal ends of the tank body.